Cocombustion of biomass and fossil fuels (FB-COMBUSTION)

Projektdetails

Gesamtkosten:

EU-Beitrag:

Koordiniert in:

Thema(en):

Finanzierungsprogramm:

BUR - Bursaries, grants, fellowships

Ziel

One of the possibilities to cut down environmental effects of energy production with fossil fuels is to partly replace coal with biomass. Combining biomass with coal full-scale boilers for electricity eneration (cocombustion) could lead to a high energy-efficiency utilisation at comparatively low investment costs. One of the main problems in cocombustion of coal and biomass is the increased deposit formation and corrosion due to increased concentration of chlorine and alkalis in the fuel mixture. The alkalis originating from the fuel ash contribute to deposit formation during the cocombustion. The increased reactivity due to increased content of volatiles in the fuel blends may promote alkali release from coal in the flame thus strengthening the deposit formation even if the contents of alkalis, chlorine and sulphur were not high in the biomass. The increased mineral content in the fuel blends 'originated from biomass) may also promote fouling. At the moment FB boilers are the most advantageous burner systems due to their ability to burn wide assortment of fuels and still provide reduced emissions. The temperature in a fluidised bed is lower that in pulverized fuel combustion and efficient combustion is achieved by a relatively long residence time in the bed. Because of the relatively low temperature, the thermal NOx formation is not a problem in FB. The fellows will in their work concentrate on - cocombustion of biomass and fossil fuels - deposit formation and - corrosion